K. R. Bestgen, K. A. Zelasko, and G. C. White. Monitoring ...

about 30 mm TL and about 100 mm TL have been captured in backwaters or the main channel of
the lower Green River by seining or electrofishing, respectively (Gutermuth et al. 1994; P.
Badame pers. comm., detailed in Bestgen et al. 2011). Care should be taken when identifying
such specimens and minimally, high quality and close-up digital photographs should be taken
that include the lateral view of the body as well as the ventral view of the mouth. Any sampling
mortalities should be preserved immediately, preferably in 100% ethanol, so that additional
verification and other analyses (e.g., otolith increment counts) can be conducted.
Additional sampling of early life history stages of suckers was proposed in the Larval
Trigger Study Plan (LaGory et al. 2012) and we offer some guidelines to be used for razorback
sucker sampling in that program. Most early life stage sampling will occur under existing study
22f, and additional studies by the U. S. Fish and Wildlife Service and Utah Division of Wildlife
Resources (each of Vernal, Utah), and will involve sampling in or near the mouths of up to eight
target wetland breaches per year during the flow connection period (late May and June), as well
as in the immediate post-connection period (late June or July, depending on the flow level and
connection duration). The early sampling will attempt to document the entrainment and early
survival of larvae in wetlands as a first step to evaluate use of the Larval Trigger for flow
releases. That sampling will begin after first occurrence of larvae is documented downstream of
spawning areas, perhaps at Cliff Creek, during the standard sampling effort conducted under
Project 22f.
Sampling in the post-connection period is designed to document survival of larvae after
connections with the river cease. This sampling should be conducted in all target wetlands
identified for sampling that year, not just the ones where larvae were found in or near breaches.
That is recommended because larvae could be missed with light trap sampling during high water
river-floodplain connection times. Larval presence information in wetlands in the postconnection
period will then guide which backwaters and wetlands will be sampled in autumn and
then again in spring the following year. Such interval-based sampling will allow assessment of
survival in the critical summer to autumn and overwinter periods. Wetland selection and timing
of sampling each year will be guided by anticipated flow level and duration; wetlands with lower
breach elevations (e.g., more frequent inundation) will be sampled in many or most years and
those with higher breach elevations only during higher flow years. Sampling in some of those
wetlands in the post-connection period was conducted in autumn 2011, and wild-produced (not
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